Field of the Disclosure
Various features may relate to an integrated device, and more specifically to an integrated device that includes an embedded package on package (PoP) device.
Background
Mobile devices, such as smart phones, tablets, Internet of Things (IoT), etc., require a multitude of components, chipsets, and the like. Typically, these components are provided on a printed circuit board with one or more integrated circuits. Packaging these components together into a product is becoming increasingly challenging. FIG. 1 illustrates an integrated device 100 that includes a printed circuit board (PCB) 102, a first integrated circuit (IC) package 104, a second integrated circuit (IC) package 106, a passive component 108 (e.g., capacitor), and a cover 130. The first integrated circuit (IC) package 104, the second integrated circuit (IC) package 106, and the passive component 108 are coupled to the printed circuit board (PCB) 102.
The cover 130 is coupled to the printed circuit board (PCB) 102. The cover 130 may be a metallic material that covers and protects the first integrated circuit (IC) package 104, the second integrated circuit (IC) package 106, and the passive component 108, from an external environment. The use of the cover 130 results in a void in the integrated device 100. Thus, there is wasted space in the integrated device 100. This wasted space in the integrated device 100 limits how small the integrated device 100 can be, which in turns, limits the type of devices in which the integrated device may be implemented.
Reducing the size of an integrated device poses several technical hurdles and challenges. First, as integrated circuits (ICs) are packed closer to each other, they begin to substantially interfere with one another, which may result in one or more non-functioning ICs. Second, packing the ICs closer in an integrated device may cause structural defects, which can result in a defective or non-functioning integrated device.
FIG. 2 illustrates an example of such a defect when ICs are packed close together. As shown, FIG. 2 illustrates a package on package (PoP) device 200 that includes a first package 202, a second package 204 and a void 290. The first package 202 includes a first die 220, a first package substrate 222, and a first encapsulation layer 250. The first package substrate 222 includes a first plurality of pads 224 and a first pad 226. The first die 220 is coupled to the first package substrate 222 through a first plurality of solder balls 228. Specifically, the first die 220 is coupled to the first plurality of pads 224 through the first plurality of solder balls 228. A second plurality of solder balls 236 is coupled to the first package substrate 222.
The second package 204 includes a second die 240, a second package substrate 242, a second pad 246, a third plurality of solder balls 256, and a second encapsulation layer 260. The second die 240 is coupled to the second package substrate 242. The second package 204 is coupled to the first package 202 through the third plurality of solder balls 256. For example, the third plurality solder balls 256 is coupled to the first pad 226 of the first package substrate 222, and the second pad 246 of the second package 204.
FIG. 2 illustrates a void 290 between the first die 220 and the second package substrate 242 of the second package 204. The void 290 is a space in the first encapsulation layer 250. The void 290 may occur when the gap or space between the first die 220 and the second package substrate 242 is too small or narrow to allow the first encapsulation layer 250 to completely flow in between the first die 220 and the second package substrate 242.
The presence of the void 290 can cause warpage and/or deformation (as illustrated by the arrow) in the package on package (PoP) device 200 because of the lack of structural support around that space. One undesirable side effect of the warpage and/or deformation are the weak joints and/or open joints that may occur between the third plurality of solder balls 256 and the first pad 226 and the second pad 246. For example, as shown in FIG. 2, the warpage and/or deformation of the package on package device (PoP) 200 causes increased separation between the first pad 226 and the second pad 246, which effectively stretches the third plurality of solder balls 256 (as illustrated by the arrow), and results in a weaker joint and/or open joint in the package on package (PoP) device 200. A weak joint and/or an open joint can prevent signals from properly traversing through a package on package (PoP) device, resulting in a defective package on package (PoP) device. Thus, to avoid this negative effect, the gap or space between the first die 220 and the second package substrate 242 has to increase, which effectively increases the size of the package on package (PoP) device 200, which is not desirable.
It is desirable to reduce the size, height and/or spaces of devices and packages, so that these devices and packages are placed in smaller devices. Ideally, such a device or package will have a better form factor, be cheaper to fabricate, while at the same time meeting the needs and/or requirements of mobile devices, Internet of things (IoT) devices, and/or wearable devices.